The ZA alloys , like 3, 5 and 7, are based on the zinc-aluminum
alloy system, with higher aluminum and copper contents. The other
alloying element is magnesium. This common alloy system gives the
ZA alloys several characteristics in common with the zinc alloy
group:
The three alloying elements have essentially the same effect on
alloy properties.
Iron, lead, cadmium and tin are also undesirable, and are held to
essentially the same limits.
The high purity requires the use of primary zinc at 99.990% purity.
